All-pass phase shifter

Abstract

The invention provides an all-pass phase shifter. The phase shifter comprises a first all-pass phase shifting unit and a second all-pass phase shifting unit, wherein the frequency points of the first all-pass phase shifting unit and the second all-pass phase shifting unit are different; each of the first all-pass phase shift unit and the second all-pass phase shift unit comprises a plurality of inductors connected in series; the inductor comprises a wire wound in the circumferential direction. One inductor of the first all-pass phase shift unit is coupled with one inductor of the second all-pass phase shift unit, and the other inductor of the first all-pass phase shift unit is coupled with the other inductor of the second all-pass phase shift unit; and in the mutually coupled inductors, the projections of the areas enclosed by the outer contours of the respective outermost leads in the lamination direction of the metal layers are at least partially overlapped. The phase shifter is high in phase flatness, wider in working bandwidth, small in area and high in integration level.

Description

Technical Field

[0001] This application relates to semiconductor technology, and more particularly to an all-pass phase shifter. Background Technology

[0002] An all-pass phase shifter is a circuit or device capable of continuously changing the phase of a radio frequency (RF) signal. It achieves phase shifting by changing the value of its internal variable capacitor. All-pass phase shifters can achieve phase changes of arbitrary precision without quantization error. They are crucial for scenarios requiring extremely high-precision beam control and are therefore widely used in phased array radar, instrumentation, satellite communications, medical imaging, and other fields.

[0003] Traditional phase-shifting structures include low-pass, high-pass, and all-pass phase-shifting units. The low-pass structure has a large high-frequency phase change range; as the equivalent voltage of the variable capacitor changes, the phase change at the output of its equivalent circuit follows the relationship with frequency: the phase change amplitude increases with higher frequencies. The high-pass structure has a large low-frequency phase change range; that is, at the output of the equivalent circuit, the phase change amplitude increases with lower frequencies. The all-pass phase-shifting unit has a "peak-shaped" phase change range.

[0004] Therefore, in broadband applications, multiple cascaded all-pass phase shifters are typically used to achieve phase shifting. If the number of all-pass phase shifters used is small, it will lead to a deterioration in phase flatness within the frequency band. However, all-pass phase shifter circuits are relatively large (using a large number of variable capacitors and inductors), and their phase shift range is limited; typically, a single all-pass phase shifter can provide a phase shift of up to ~90° at a specific frequency. Therefore, to achieve a larger phase shift range (all-pass phase shifters require an overall circuit phase shift range >360°), more all-pass phase shifters need to be cascaded, which in turn causes a deterioration in standing waves and insertion loss.

[0005] Therefore, in the actual design and implementation of all-pass phase shifters, it is necessary to consider the area constraints of the circuit and improve the maximum phase shift range without degrading the standing wave and insertion loss performance. Summary of the Invention

[0006] This invention provides a full-pass phase shifter, which aims to improve the maximum phase shift range and flatness of the full-pass phase shifter unit while reducing the circuit area.

[0007] This application provides an all-pass phase shifter, including: a first all-pass phase shift unit and a second all-pass phase shift unit, the first all-pass phase shift unit and the second all-pass phase shift unit having different frequency points; both the first all-pass phase shift unit and the second all-pass phase shift unit include multiple inductors connected in series; each inductor includes a wire wound in the circumferential direction; one inductor of the first all-pass phase shift unit is coupled to one inductor of the second all-pass phase shift unit, and another inductor of the first all-pass phase shift unit is coupled to another inductor of the second all-pass phase shift unit; among the coupled inductors, the regions enclosed by the outer contours of their respective outermost wires at least partially overlap in the projection of the metal layer stacking direction.

[0008] In this scheme, the first full-pass phase shifter and the second full-pass phase shifter are configured to operate at different center frequencies, and through frequency point misalignment design, they jointly cover a wider operating frequency band.

[0009] The inductors of the first and second all-pass phase shifters are cross-coupled. This coupling introduces equivalent mutual inductance into the equivalent circuit. The presence of mutual inductance increases the order of the all-pass phase shifter, giving its phase-frequency response characteristics more tunable parameters (dimensions). On the one hand, multi-order phase tuning increases the poles of the transfer function, making the phase change within the frequency band smoother and improving phase flatness. On the other hand, multi-order phase tuning expands the maximum phase shift range and supports a wider operating bandwidth.

[0010] The regions where the inductors are coupled overlap at least partially. This strengthens and stabilizes the coupling strength (coefficient) between the coupled inductor pairs, thereby improving the frequency flatness of the phase-shift response. Furthermore, by sharing layout space, the total area required for each discrete inductor to be placed individually is reduced. Simultaneously, the overlapping layout of the coupled inductors facilitates coordinated arrangement with the capacitors, further reducing the overall area occupied by the inductors and capacitors.

[0011] Furthermore, due to the increased maximum phase shift range and bandwidth of a single phase shifting network (including the first and second all-pass phase shifting units), the number of cascaded phase shifting networks required to achieve the total phase shift range and bandwidth demanded by the system is reduced. This reduction in the number of cascaded networks directly lowers the cumulative insertion loss caused by multiple phase shifting networks connected in series and mitigates the voltage standing wave ratio (VSWR) degradation resulting from multiple impedance transformations, thereby contributing to improved insertion loss and VSWR performance of the entire all-pass phase shifter. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the circuit structure of an all-pass phase shifter in related technologies;

[0013] Figure 2 This is a schematic diagram of the layout structure of an all-pass phase shifter in related technologies;

[0014] Figure 3 The simulated phase-shifting characteristic curves of all-pass phase shifters in related technologies are shown.

[0015] Figure 4 This is a schematic diagram of the circuit structure of an all-pass phase shifter provided in Embodiment 1 of this disclosure;

[0016] Figure 5 for Figure 4 The equivalent circuit diagram of an all-pass phase shifter;

[0017] Figure 6 This is a schematic diagram of the layout structure of an all-pass phase shifter provided in Embodiment 1 of this disclosure;

[0018] Figure 7 This is a phase comparison diagram of the all-pass phase shifter according to Embodiment 1 of this application and all-pass phase shifters in related technologies;

[0019] Figure 8 This is a schematic diagram of another mutually coupled inductor layout structure provided in Embodiment 2 of this disclosure;

[0020] Figure 9 This is a schematic diagram of another mutually coupled inductor layout structure provided in Embodiment 3 of this disclosure;

[0021] Figure 10 This is a schematic diagram of another mutually coupled inductor layout structure provided in Embodiment 4 of this disclosure;

[0022] Figure 11 This is a schematic diagram of another mutually coupled inductor layout structure provided in Embodiment 5 of this disclosure;

[0023] Figure 12 This is a schematic diagram of another mutually coupled inductor layout structure provided in Embodiment Six of this disclosure;

[0024] Figure 13 This is a schematic diagram of the circuit structure of another all-pass phase shifter provided in Embodiment 7 of this disclosure;

[0025] Figure 14 This is a schematic diagram of the layout structure of another all-pass phase shifter provided in Embodiment 7 of this disclosure. Detailed Implementation

[0026] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the disclosure. Furthermore, it should be noted that, for ease of description, only the parts relevant to the disclosure are shown in the accompanying drawings.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used herein is for the purpose of describing embodiments of this disclosure only and is not intended to be limiting of this disclosure.

[0028] In the following description, references are made to “some embodiments,” which describe a subset of all possible embodiments. However, it is understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0029] In the following description, “connection” refers to any way of establishing an electrical signal between two device units, including but not limited to: direct connection: no functional components (such as resistors, capacitors, switches, etc.) are involved between the two units; indirect connection: one or more functional components are connected in series between the two units.

[0030] It should be noted that the terms "first, second, third" used in the embodiments of this disclosure are merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first, second, third" can be interchanged in a specific order or sequence where permitted, so that the embodiments of this disclosure described herein can be implemented in an order other than that illustrated or described herein.

[0031] In this application, the order refers to the number of independent energy storage elements (inductors and capacitors) in the circuit. For all-pass phase shifters, the higher the order, the more tunable parameters of its phase-frequency response curve, the greater the flexibility and controllability of phase changes, and the larger the phase shift range.

[0032] The transfer function specifically refers to the function that the complex ratio of the output signal to the input signal varies with frequency.

[0033] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0034] Figure 1 The circuit structure diagram of the all-pass phase shifter according to the relevant technology of this application is shown below. Figure 1 As shown, the all-pass phase shifter includes a phase shifting unit 210 and a phase shifting unit 220. The phase shifting unit 210 and the phase shifting unit 220 operate at different center frequencies. The phase shifting unit 210 includes inductors L1-L2, capacitors C1-C3 and resistor R11, and the phase shifting unit 220 includes inductors L3-L4, capacitors C4-C6 and resistor R12. Figure 2 This is a schematic diagram of the layout structure of an all-pass phase shifter in related technologies. Figure 2The layout of the all-through phase shifter occupies a large area, which is not conducive to the miniaturization and integration of the circuit.

[0035] Figure 3 The simulated phase-shifting characteristic curves of the all-pass phase shifter in related technologies show that the phase-shifting curves of phase-shifting units 210 and 220 exhibit a "peak-shaped" pattern. Phase-shifting unit 210 reaches its peak phase shift at approximately 4 GHz, while phase-shifting unit 220 reaches its peak phase shift at approximately 12 GHz. Since the phase shifts of the two phase-shifting units are superimposed in the frequency domain, the entire phase shifter can achieve a total phase shift exceeding 130° within the 4 GHz to 12 GHz frequency band, thus realizing broadband phase shifting functionality. The inventors discovered through analysis that, as... Figure 3 As shown, the phase shifter exhibits poor phase response flatness in the 4GHz to 12GHz frequency band: the maximum phase shift (point A, approximately 140°) differs from the minimum phase shift (point B, approximately 130°) by as much as 10°, resulting in significant in-band phase fluctuations and a noticeable dip in the phase shift curve at point B. Furthermore, given that the maximum phase shift of this all-pass phase shifter is 140 degrees, a larger phase shift range typically requires cascading multiple such all-pass phase shifters, leading to increased circuit complexity and insertion loss.

[0036] To address the aforementioned shortcomings, this application proposes a novel all-pass phase shifter, comprising: a first all-pass phase shift unit and a second all-pass phase shift unit, wherein the first and second all-pass phase shift units have different frequency points; both the first and second all-pass phase shift units include multiple inductors connected in series; the inductors include circumferentially wound wires; one inductor of the first all-pass phase shift unit is coupled to one inductor of the second all-pass phase shift unit, and another inductor of the first all-pass phase shift unit is coupled to another inductor of the second all-pass phase shift unit; in the coupled inductors, the regions enclosed by their respective wires at least partially overlap in the projection of the metal layer stacking direction, thereby achieving effective magnetic coupling.

[0037] In the embodiments of this application, "circumferential" refers to the geometric path around which the guide line is wound, including but not limited to circular circumferential, rectangular circumferential, or other polygonal circumferential shapes.

[0038] The following description, in conjunction with the accompanying drawings, details the all-pass phase shifter of this application.

[0039] Figure 4 This is a schematic diagram of the circuit structure of an all-pass phase shifter provided in Embodiment 1 of this disclosure. Figure 4As shown, the all-pass phase shifter 1 includes a first all-pass phase shifter unit 110 and a second all-pass phase shifter unit 120. The first all-pass phase shifter unit 110 and the second all-pass phase shifter unit 120 have different frequency points, that is, the first all-pass phase shifter unit 110 and the second all-pass phase shifter unit 120 are configured to operate at different center frequencies. The phase shifts of the first all-pass phase shifter unit 110 and the second all-pass phase shifter unit 120 are superimposed in the frequency domain, jointly covering a wider operating frequency band. In this embodiment, the first all-pass phase shifter unit 110 and the second all-pass phase shifter unit 120 are connected in series in the radio frequency signal path (the path between the radio frequency input terminal RFIN and the radio frequency output terminal RFOUT). The radio frequency signal flows through the first all-pass phase shifter unit 110 and the second all-pass phase shifter unit 120 in sequence. In other embodiments, the connection order of the first all-pass phase shifter unit 110 and the second all-pass phase shifter unit 120 can be adjusted.

[0040] Both the first full-pass phase-shifting unit 110 and the second full-pass phase-shifting unit 120 include multiple inductors connected in series; such as Figure 4 As shown, the first all-pass phase shift unit 110 includes a first inductor L1 and a second inductor L2 connected in series, with the first inductor L1 and the second inductor L2 connected in series between the input terminal A and the output terminal B of the first all-pass phase shift unit 110; the second all-pass phase shift unit 120 includes a third inductor L3 and a fourth inductor L4 connected in series, with the third inductor L3 and the fourth inductor L4 connected in series between the input terminal C and the output terminal D of the second all-pass phase shift unit 120.

[0041] Inductive cross-coupling of the all-pass phase-shifting unit: such as Figure 4 As shown, the first inductor L1 and the fourth inductor L4 are coupled together, with a coupling coefficient denoted as K1; simultaneously, the second inductor L2 and the third inductor L3 are coupled together, with a coupling coefficient denoted as K2. "Cross-coupling" refers to the coupling between one inductor of the first full-pass phase-shifting unit and one inductor of the second full-pass phase-shifting unit, and between the other inductor of the first full-pass phase-shifting unit and the other inductor of the second full-pass phase-shifting unit. In some embodiments, the first inductor L1 may also be coupled to the third inductor L3, while the second inductor L2 and the fourth inductor L4 are coupled together. The following explanation uses the coupling between the first inductor L1 and the fourth inductor L4, and the coupling between the second inductor L2 and the third inductor L3, as examples.

[0042] Continue to refer to Figure 4 The first all-pass phase shifting unit 110 and the second all-pass phase shifting unit 120 further include: a parallel adjustable capacitor and a series adjustable capacitor; the parallel adjustable capacitor is connected in parallel with the corresponding inductor; one end of the series adjustable capacitor is connected to the corresponding inductor, and the other end is grounded.

[0043] Specifically, in this embodiment, the first all-pass phase-shifting unit 110 includes a first parallel adjustable capacitor C1 and a second parallel adjustable capacitor C2. The first parallel adjustable capacitor C1 and the second parallel adjustable capacitor C2 are connected in series and then in parallel with the branch containing the first inductor L1 and the second inductor L2. That is, the first parallel adjustable capacitor C1 and the second parallel adjustable capacitor C2 are connected across the input terminal A and the output terminal B. The parallel adjustable capacitors can provide a low-impedance path for the signal at high frequencies, which helps to expand the bandwidth and achieve all-pass characteristics. In addition, the first all-pass phase-shifting unit 110 also includes a series adjustable capacitor C3. One end of the series adjustable capacitor C3 is connected to the node between the first inductor L1 and the second inductor L2, and the other end of the series adjustable capacitor C3 is grounded. The series adjustable capacitor C3 is used to provide a reliable ground for the first inductor L1 and the second inductor L2.

[0044] The second all-pass phase-shifting unit 120 includes a third parallel adjustable capacitor C5 and a fourth parallel adjustable capacitor C6. These two capacitors are connected in series and then in parallel with the branch containing the third inductor L3 and the fourth inductor L4. In other words, the third and fourth parallel adjustable capacitors C5 and C6 are connected together across the input terminal C and the output terminal D, providing a low-impedance path for high-frequency signals. Furthermore, the second all-pass phase-shifting unit 120 also includes a series adjustable capacitor C4. One end of the series adjustable capacitor C4 is connected to the node between the third inductor L3 and the fourth inductor L4, and the other end is grounded. The series adjustable capacitor C4 provides a reliable ground for the third inductor L3 and the fourth inductor L4.

[0045] It should be noted that the above capacitor connection methods (such as the combination of parallel and series adjustable capacitors, and the selection of grounding points) are one specific implementation of this scheme. Within the scope of this scheme, the capacitors can adopt other topologies: for example, using a single adjustable capacitor to replace the series parallel capacitor pair; or not using a series adjustable capacitor, and grounding the node between the first inductor L1 and the second inductor L2 through a wire, etc.

[0046] like Figure 4 As shown, the first all-pass phase shifting unit 110 further includes a first resistor R11. One end of the first resistor R11 is connected to the node between the first parallel adjustable capacitor C1 and the second parallel adjustable capacitor C2, and the other end of the first resistor R11 is grounded, used to provide DC bias for the parallel adjustable capacitors. The second all-pass phase shifting unit 120 further includes a second resistor R12. One end of the second resistor R12 is connected to the node between the third parallel adjustable capacitor C5 and the fourth parallel adjustable capacitor C6, and the other end of the second resistor R12 is grounded, used to provide DC bias for the parallel adjustable capacitors.

[0047] Figure 5 for Figure 4The equivalent circuit diagram of an all-pass phase shifter. (Example) Figure 5 As shown, the first inductor L1 and the fourth inductor L4, which are coupled together, are equivalent to equivalent inductance Leq1, equivalent inductance Leq2, and equivalent mutual inductance M1. Similarly, the second inductor L2 and the third inductor L3, which are coupled together, are equivalent to equivalent inductance Leq3, equivalent inductance Leq4, and equivalent mutual inductance M2. The first parallel adjustable capacitor C1, the second parallel adjustable capacitor C2, the third parallel adjustable capacitor C5, and the fourth parallel adjustable capacitor C6 are equivalent to equivalent capacitors Ceq1 and Ceq2, and the series adjustable capacitors C3 and C4 are equivalent to equivalent capacitors Ceq3 and Ceq4.

[0048] In this embodiment, the parameter relationships of each device in the equivalent circuit of the all-pass phase shifter are as follows:

[0049] Leq1 = L1 − M1;

[0050] Leq2 = L4 − M1;

[0051] ;

[0052] Leq3 = L3−M2;

[0053] Leq4 = L2−M2;

[0054] ;

[0055] Wherein, L1-L4 are the inductances of the first to fourth inductors, Leq1-Leq4 are the inductances of the four equivalent inductors, and M1 and M2 are the inductances of the equivalent mutual inductances M1 and M2, respectively.

[0056] In this scheme, the two pairs of inductors in the first and second all-pass phase shifting units are cross-coupled. This coupling method introduces equivalent mutual inductances M1 and M2 into the equivalent circuit. The presence of mutual inductance increases the order of the all-pass phase shifter, which gives its phase-frequency response characteristics more tunable parameters (dimensions). On the one hand, multi-order phase tuning increases the poles of the transfer function, making the phase change within the frequency band smoother and improving phase flatness; on the other hand, multi-order phase tuning expands the maximum phase shift range and supports a wider operating bandwidth.

[0057] Furthermore, due to the increased maximum phase shift range and bandwidth of a single phase shifting network (including the first and second all-pass phase shifting units), the number of cascaded phase shifting networks required to achieve the total phase shift range and bandwidth demanded by the system is reduced. This reduction in the number of cascaded networks directly lowers the cumulative insertion loss caused by multiple phase shifting networks connected in series and mitigates the voltage standing wave ratio (VSWR) degradation resulting from multiple impedance transformations, thereby contributing to improved insertion loss and VSWR performance of the entire all-pass phase shifter.

[0058] Figure 6 This is a schematic diagram of the layout structure of an all-pass phase shifter provided in Embodiment 1 of this disclosure; in the layout structure, each inductor includes a wire wound in the circumferential direction. Figure 6 As shown, in the all-pass phase shifter of this embodiment, the first inductor L1 includes a circumferentially wound wire 111; the second inductor L2 includes a circumferentially wound wire 112; the third inductor L3 includes a circumferentially wound wire 122; and the fourth inductor L4 includes a circumferentially wound wire 121. Figure 6 In the layout diagram, the first and second resistors are not shown to clearly illustrate the arrangement of inductors and capacitors.

[0059] To achieve the required coupling relationships in the circuit, the layout must satisfy the following relationships:

[0060] The region enclosed by the outer contour of the outermost conductor 111 of the first inductor L1 is denoted as R1, and the region enclosed by the outer contour of the outermost conductor 121 of the fourth inductor L4 is denoted as R4. The projections of regions R1 and R4 in the metal layer stacking direction at least partially overlap, that is, in Figure 6 On the planar layout shown, regions R1 and R4 overlap at least partially to ensure effective magnetic coupling between the first inductor L1 and the fourth inductor L4.

[0061] The region enclosed by the outer contour of the outermost conductor 112 of the second inductor L2 is denoted as R2, and the region enclosed by the outer contour of the outermost conductor 122 of the third inductor L3 is denoted as R3. The projections of regions R2 and R3 in the metal layer stacking direction at least partially overlap, that is, in Figure 6 On the planar layout shown, regions R2 and R3 overlap at least partially to ensure effective magnetic coupling between the second inductor L2 and the third inductor L3.

[0062] The regions where the inductors are coupled overlap at least partially (regions R1 and R4 overlap at least partially, and regions R2 and R3 overlap at least partially). This strengthens and stabilizes the coupling strength (coefficient) between the coupled inductor pairs, thereby improving the frequency flatness of the phase-shift response. Furthermore, by sharing layout space, the total area required for each discrete inductor to be arranged individually is reduced. Simultaneously, the overlapping layout of the coupled inductors facilitates coordinated arrangement with the capacitor regions, further reducing the overall area occupied by the inductors and capacitors.

[0063] like Figure 6 As shown, in this embodiment, the RF input terminal RFIN and the RF output terminal RFOUT are arranged along the second direction (denoted as the X direction); the arrangement direction of one inductor (first inductor L1) and the other inductor (second inductor L2) of the first all-pass phase shift unit is the first direction (Y direction). The second direction X intersects the first direction Y, for example, the second direction X is perpendicular or substantially perpendicular to the first direction Y. That is, the inductance pair formed by the first inductor L1 (and its coupled object L4) and the inductance pair formed by the second inductor L2 (and its coupled object L3) are arranged sequentially along the first direction (Y direction) perpendicular to the second direction. This orthogonal arrangement in the X direction fully utilizes the two-dimensional XY plane space, achieving a more compact layout overall and reducing the chip area.

[0064] In terms of the coupling layout of the inductors, this embodiment adopts a same-layer coupling scheme: in at least one mutually coupled inductor, at least a portion of the conductors of the different inductors are located in the same metal layer. For example, in Figure 6 In this configuration, the conductor 111 of the first inductor L1 and the conductor 121 of the fourth inductor L4 are located in the same metal layer, as are the conductors 112 of the second inductor L2 and the conductor 122 of the third inductor L3. The high precision control of parameters such as conductor spacing and linewidth within the same metal layer makes it easier to predict and control the parasitic capacitance parameters between the coupled inductors. This prevents parasitic resonances at unexpected frequency points, thereby ensuring the integrity of the target operating bandwidth and the stability of performance.

[0065] In some embodiments, to further enhance the magnetic coupling strength between mutually coupled inductors, a nested winding layout structure can be employed. Specifically, in at least one mutually coupled inductor, the wires of different inductors are nested in a manner such that the winding path of one inductor's wire at least partially surrounds the winding path of the other inductor's wire; that is, a corresponding segment of one wire is located outside the other wire, forming an enclosing relationship. This enclosing relationship can be full enclosing or partial enclosing (semi-enclosing). Figure 6As shown, in this embodiment, the wire 111 of the first inductor L1 and the wire 121 of the fourth inductor L4 are nested and wound, with the winding path of wire 111 at least partially surrounding the winding path of wire 121, and a portion of wire 111 being located outside the corresponding segment of wire 121; similarly, the wire 112 of the second inductor L2 and the wire 122 of the third inductor L3 are nested and wound, with the winding path of wire 112 at least partially surrounding the winding path of wire 122, and a portion of wire 112 being located outside the corresponding segment of wire 122. The nested winding of the inductor wires increases the mutual inductance area between adjacent wires, thereby significantly improving the coupling coefficient between the inductor pairs. In some embodiments, only one pair of mutually coupled inductors may be nested and wound, such as the nested winding of the wire 111 of the first inductor L1 and the wire 121 of the fourth inductor L4, or the nested winding of the wire 112 of the second inductor L2 and the wire 122 of the third inductor L3.

[0066] As a specific implementation of nested winding, in some embodiments, the winding path of the wires of the two coupled inductors can be achieved by alternating spiral windings to at least partially surround the wires of the other inductor. Specifically, in at least one coupled inductor, the wires of different inductors alternately spiral wound; in the coupled inductors, the two wires are wound alternately side by side in the same direction of rotation to form a coplanar spiral path. Figure 6 As shown, in this embodiment, the wires 111 of the first inductor L1 and 121 of the fourth inductor L4 are alternately spiraled; the wires 112 of the second inductor L2 and 122 of the third inductor L3 are alternately spiraled. The alternating spiraling of the inductor wires not only maximizes the parallel length between the two wires, enhancing magnetic coupling, but also reduces the overall footprint. Simultaneously, the alternating spirals ensure a uniform distribution of the coupling region, contributing to a flatter frequency response and further extending the operating bandwidth. In some embodiments, only one pair of mutually coupled inductors may be alternately spiraled, such as the wires 111 of the first inductor L1 and 121 of the fourth inductor L4, or the wires 112 of the second inductor L2 and 122 of the third inductor L3.

[0067] In some embodiments, the wires between the same coupled inductor pairs maintain a uniform spacing along the winding path. Specifically, such as Figure 6As shown, in each turn of the alternating spiral of wires 111 and 121, the edge-to-edge distance between them remains constant, and the spacing between any adjacent segments of wires 111 and 121 is consistent; similarly, the spacing between wires 112 and 122 is also equal everywhere. This uniform spacing design keeps the parasitic capacitance per unit length of wire constant, avoiding high-frequency resonance or phase distortion caused by sudden changes in local capacitance, and improving in-band flatness. In some embodiments, only a pair of wires with mutually coupled inductance may maintain a uniform spacing on the winding path, for example, a uniform spacing between wires 111 and 121, or a uniform spacing between wires 112 and 122.

[0068] In some embodiments, the distance between the wires is 6 micrometers to 20 micrometers, such as 10 micrometers or 15 micrometers. Too small a distance leads to excessive parasitic capacitance, compressing the available bandwidth and worsening phase flatness; too large a distance weakens the magnetic coupling strength and reduces phase-shifting efficiency. A distance of 6 micrometers to 20 micrometers effectively suppresses parasitic effects while maintaining a strong coupling coefficient, balancing performance and reliability.

[0069] To further optimize coupling efficiency and layout compactness, in some embodiments, the central axes of the wires in at least one coupled inductor coincide; that is, the coupled pair of inductors are wound with a common central axis. For example... Figure 6 As shown, in this embodiment, wires 111 and 121 rotate around the same central axis O1, and wires 112 and 122 rotate around the same central axis O2. This common-axis winding not only maximizes the coupling coefficient but also further saves chip area.

[0070] like Figure 6 As shown, in this embodiment, series adjustable capacitors C3 and C4 are arranged in the second direction X. Since the physical size of capacitors is usually much smaller than that of inductors, the arrangement of series adjustable capacitors C3 and C4 utilizes the layout space in the X direction and helps to reduce the size in the Y direction.

[0071] Both series adjustable capacitors C3 and C4 need to be grounded. After series adjustable capacitors C3 and C4 are arranged in the second direction X, they can be conveniently arranged adjacent to each other to share the same grounding node 131, thereby saving the number of grounding nodes and further reducing the area.

[0072] like Figure 6As shown, the first inductor L1, the series adjustable capacitor C3, and the second inductor L2 are arranged sequentially in the first direction. That is, the inductor pair consisting of the first inductor L1 and the fourth inductor L4, the series adjustable capacitors C3 and C4, and the inductor pair consisting of the second inductor L2 and the third inductor L3 are arranged sequentially along the first direction (Y direction). This sequential arrangement makes the electrical connection paths of each device as short and straight as possible, reducing parasitic capacitance on the signal path, thereby improving phase flatness.

[0073] In some embodiments, such as Figure 6 As shown, the parallel adjustable capacitors C1, C2, C5, and C6 are arranged in the second direction X. The inductance pair formed by the first inductor L1 and the fourth inductor L4, the series adjustable capacitors C3 and C4, the second inductor L2 and the third inductor L3 are all located on the same side of the parallel adjustable capacitors C1, C2, C5, and C6. This ensures that the connection lines between the inductors and capacitors, between the inductors and the RF input terminal RFIN, or between the inductors and the RF output terminal RFOUT do not need to cross the branch where the RF input terminal, the parallel adjustable capacitors, and the RF output terminal are located, or detour. The path is shorter and the parasitic capacitance is reduced.

[0074] Compared to Figure 2 Compared to the conventional solution shown, the layout area of ​​this embodiment is reduced by about 40%, which improves the chip integration.

[0075] To effectively cover a wide bandwidth, in some embodiments, the frequency of one phase-shifting unit is 1.5 to 4 times, for example, 2 or 3 times, the frequency of another phase-shifting unit. Specifically, the frequency of the first all-pass phase-shifting unit 110 is 1.5 to 4 times the frequency of the second all-pass phase-shifting unit 120, or the frequency of the second all-pass phase-shifting unit 120 is 1.5 to 4 times the frequency of the first all-pass phase-shifting unit 110. As a specific example, the frequency of the first all-pass phase-shifting unit 110 is 4 GHz, and the frequency of the second all-pass phase-shifting unit 120 is 12 GHz. In this configuration, the phase response curves of the two units form a complementary superposition within the 4 GHz to 12 GHz frequency band, enabling the entire all-pass phase shifter to achieve continuous, wide-range, and highly flat phase adjustment within this frequency band.

[0076] Figure 7 This is a phase comparison diagram of the all-pass phase shifter according to Embodiment 1 of this application and related all-pass phase shifters. The horizontal axis represents frequency (GHz), the vertical axis represents phase (deg), and the coordinate axis represents degrees (°). The solid curve is... Figure 1 The phase curve of the all-pass phase shifter is shown in the figure, with the dashed curve representing the phase curve of the all-pass phase shifter in this application. Figure 7As shown, in the range of 4GHz to 12GHz, the phase curve of the all-pass phase shifter of the related technology fluctuates significantly, with the maximum and minimum phase shift angles differing by 10 degrees; while the phase curve of the present application is relatively smooth, with in-band phase fluctuation of less than 1° and high phase flatness.

[0077] Furthermore, the maximum phase shift achievable by related technologies within this frequency band is 140°. The maximum phase shift of the scheme in this application is increased to 160°, an increase of 20°, resulting in a wider phase shift range.

[0078] Figure 8 This is a schematic diagram of another mutually coupled inductor layout structure provided in Embodiment 2 of this disclosure; the difference between this embodiment and Embodiment 1 is that it provides another arrangement of mutually coupled inductor layouts.

[0079] In this embodiment, the conductors of the mutually coupled inductor pairs utilize different metal layers in certain regions. For example... Figure 8 As shown, most of the conductors 121 of the fourth inductor L4 and the conductors 111 of the first inductor L1 are located on the same metal layer, while the overlapping portion 132 of the fourth inductor L4 is located on a different metal layer and is wound with jumpers. It should be understood that the conductors of the second inductor L2 and the third inductor L3 can also have overlapping portions located on different metal layers and be wound with jumpers.

[0080] Figure 9 This is a schematic diagram of another mutually coupled inductor layout structure provided in Embodiment 3 of this disclosure; the difference between this embodiment and Embodiment 1 is that it provides another arrangement of mutually coupled inductor layouts.

[0081] In this embodiment, the inductor pairs are formed by non-alternating spiral winding of the wires of the two inductors. Alternatively, multiple layers of wires from one inductor can be nested within a single layer of wires from another inductor, or a single layer of wires from one inductor can be nested within multiple layers of wires from another inductor. Figure 9 As shown, in this embodiment, the two inductors constituting the mutually coupled inductor pair adopt a nested layout of "two layers within one layer". Specifically, a portion of the two layers of conductors 121 is located outside the first layer of conductor 111, and a portion of the two layers of conductors 111 is located outside the first layer of conductor 121, forming an overlapping, looping structure. The portions 132 of the inductors at the overlapping positions are located on different metal layers and are wound via jumpers.

[0082] It should be understood that the second inductor L2 and the third inductor L3 can also be used. Figure 9 The layout shown.

[0083] Figure 10This is a schematic diagram of another mutually coupled inductor layout structure provided in Embodiment 4 of this disclosure; the difference between this embodiment and Embodiment 1 is that it provides another arrangement of mutually coupled inductor layouts.

[0084] In this embodiment, a pair of inductors are formed by mutual coupling, with the wire of one inductor wrapped around the outside of the wire of the other inductor, forming an enclosing structure. For example... Figure 9 As shown, in this embodiment, the wire 121 of the fourth inductor L4 is located on the outer winding path, and the wire 111 of the first inductor L1 is located on the inner winding path. The outer wire 121 is completely wrapped around the outer periphery of the inner wire 111.

[0085] It should be understood that the second inductor L2 and the third inductor L3 can also be used. Figure 10 The layout shown.

[0086] Figure 11 This is a schematic diagram of another mutually coupled inductor layout structure provided in Embodiment 5 of this disclosure; the difference between this embodiment and Embodiment 1 is that it provides another arrangement of mutually coupled inductor layouts.

[0087] In this embodiment, the wires of the mutually coupled inductor pairs are respectively fabricated on different metal layers. For example... Figure 11 As shown, the Z-direction represents the stacking direction of different metal layers. The wire 121 of the fourth inductor L4 and the wire 111 of the first inductor L1 are located in different metal layers. The wire 111 of the first inductor L1 is located in the upper metal layer, and the wire 121 of the fourth inductor L4 is located in the lower metal layer. The projections of the first inductor L1 and the fourth inductor L4 overlap, resulting in stronger magnetic coupling, more stable electromagnetic interaction, good consistency of phase change with frequency, and high flatness. Furthermore, the overlapping projections of the inductors in different metal layers can further save planar area. It should be understood that the wire 121 of the fourth inductor L4 can be located in the upper layer, and the wire 111 of the first inductor L1 can be located in the lower layer. In addition, the wires of the second inductor L2 and the third inductor L3 can also be located in different metal layers.

[0088] like Figure 11 As shown, the wire 121 of the fourth inductor L4 and the wire 111 of the first inductor L1 are located in different metal layers, so that the inductor winding center (as shown) Figure 11The area containing the dotted coil has a large unconducted region that can be reused to place other components. For example, series adjustable capacitors C3 and / or C4 can be embedded in the center of the first inductor L1 or the fourth inductor L4, further saving planar area. For example, series adjustable capacitor C3 can be located at the center of the first inductor L1, and / or series adjustable capacitor C4 can be located at the center of the fourth inductor L4; or series adjustable capacitor C4 can be located at the center of the first inductor L1, and / or series adjustable capacitor C3 can be located at the center of the fourth inductor L4; series adjustable capacitor C3 can be located at the center of the second inductor L2, series adjustable capacitor C4 can be located at the center of the third inductor L3, and so on. In other embodiments, when the conductors in the mutually coupled inductors are at least partially located in the same metal layer, the unconducted region at the center of the inductor winding can also be used to place the series adjustable capacitor.

[0089] exist Figure 11 In the case of mutually coupled inductor pairs (such as the first inductor L1 and the fourth inductor L4), the projections of wires 111 and 121 in the direction of metal layer stacking surround the same central axis O1.

[0090] In other embodiments, the mutual coupling inductors of different metal layers can be arranged in a staggered manner. Figure 12 This is a schematic diagram of another mutually coupled inductor layout structure provided in Embodiment Six of this disclosure; in Figure 12 In this configuration, wire 111 is wound around a central axis O1, and wire 121 is wound around another central axis O2. It should be understood that the second inductor L2 and the third inductor L3 can also be... Figure 12 The layout shown.

[0091] Figure 13 This is a schematic diagram of the circuit structure of another all-pass phase shifter provided in Embodiment 7 of this disclosure; Figure 14 This is a schematic diagram of the layout structure of another all-pass phase shifter provided in Embodiment Seven of this disclosure; the difference between this embodiment and Embodiment One is that it provides another circuit structure of an all-pass phase shifter.

[0092] In this embodiment, as Figure 13 As shown, the all-pass phase shifter 1 in this embodiment includes multiple phase shifting networks (including a first all-pass phase shifting unit and a second all-pass phase shifting unit). These multiple phase shifting networks are sequentially connected between the RF input terminal RFIN and the RF output terminal RFOUT, further increasing the phase shifting range and bandwidth. For example, two phase shifting networks sequentially connected between the RF input terminal RFIN and the RF output terminal RFOUT can achieve 360° phase shifting.

[0093] like Figure 14As shown, multiple phase-shifting networks are arranged sequentially in the second direction X. Because the width of the phase-shifting network in the second direction X is small, multiple phase-shifting networks can be arranged sequentially with low loss along the signal flow direction (second direction X). It should be understood that the inductors coupled to each other in the phase-shifting network can be used... Figures 8 to 12 The arrangement of the phase-shifting networks; the layouts of different phase-shifting networks can be the same or different.

[0094] It should be noted that, in this disclosure, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0095] The sequence numbers of the embodiments disclosed above are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0096] The features disclosed in the several embodiments provided in this disclosure can be combined arbitrarily without conflict to obtain new embodiments.

[0097] The above are merely specific embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A full-pass phase shifter, characterized in that, include: The first full-pass phase shift unit and the second full-pass phase shift unit have different frequency points; Both the first full-pass phase-shifting unit and the second full-pass phase-shifting unit include multiple inductors connected in series; the inductors include wires wound in the circumferential direction; One inductor of the first full-pass phase-shifting unit is coupled to one inductor of the second full-pass phase-shifting unit, and the other inductor of the first full-pass phase-shifting unit is coupled to the other inductor of the second full-pass phase-shifting unit; In mutually coupled inductors, the regions enclosed by the outer contours of their respective outermost conductors at least partially overlap in the projection of the metal layers in the stacking direction.

2. The all-pass phase shifter according to claim 1, characterized in that, In at least one of the said mutually coupled inductors, the conductors of the different inductors are located in different metal layers or at least partially in the same metal layer, and the winding path of the conductor of one inductor at least partially surrounds the winding path of the conductor of the other inductor.

3. The all-pass phase shifter according to claim 2, characterized in that, In at least one of the said mutually coupled inductors, the wires of the different inductors achieve at least partial encirclement in an alternating spiral manner.

4. The all-pass phase shifter according to claim 1, characterized in that, The first full-pass phase-shifting unit and / or the second full-pass phase-shifting unit further include a series adjustable capacitor, which is located in the wire-free region at the center of the inductor winding.

5. The all-pass phase shifter according to any one of claims 1 to 4, characterized in that, In at least one of the said mutually coupled inductors, the wires maintain a uniform spacing along the winding path; the distance between the wires is 6 micrometers to 20 micrometers; and / or, In at least one of the mutually coupled inductors, the central axes of the wires are coincident.

6. The all-pass phase shifter according to claim 1, characterized in that, One inductor of the first full-pass phase-shifting unit and another inductor of the first full-pass phase-shifting unit are arranged in a first direction; Both the first full-pass phase-shifting unit and the second full-pass phase-shifting unit further include: a parallel adjustable capacitor and a series adjustable capacitor; the parallel adjustable capacitor is connected in parallel with the corresponding inductor; One end of the series adjustable capacitor is connected to the corresponding inductor, and the other end is grounded.

7. The all-pass phase shifter according to claim 6, characterized in that, The series adjustable capacitor in the first full-pass phase-shifting unit and the series adjustable capacitor in the second full-pass phase-shifting unit are arranged in a second direction; wherein the second direction intersects the first direction.

8. The all-pass phase shifter according to claim 6, characterized in that, The series adjustable capacitor in the first full-pass phase-shifting unit and the series adjustable capacitor in the second full-pass phase-shifting unit share the same grounding node.

9. The all-pass phase shifter according to claim 6, characterized in that, The series adjustable capacitor is connected between one inductor and the other inductor of the first all-pass phase shift unit.

10. The all-pass phase shifter according to claim 6, characterized in that, The inductor and the series adjustable capacitor are located on the same side of the parallel adjustable capacitor.

Images